Driveshaft Lengths- need help

[7693000079]

I am installing a 915 transaxle from an 85 into my 72. The stub axle is the 4 bolt, 2 dowel style while the transaxle is the six bolt style. I took 3 pairs of driveshafts to the rebuild shop to have them make one good set with a 4 bolt end and 6 bolt on the other end. The shop called back and said my shafts are different lengths. 19 1/8 (486mm) vs. 18 3/4 (476mm). Can someone tell me which ones I should be using. Thanks, Barrett

[jluetjen]

What sort of trailing arms are you using? Aluminum or steel.

[7693000079]

T-arms are stock 73 steel.

[jluetjen]

I'm not sure if you'll be able to mix the ends of the CV joints with the half shafts. When I replaced my steel trailing arms with aluminums from a '76, I had to replace the outer CV's because the CV's that I used with the steel arms interfered with the aluminum arms. I couldn't mix the CV's on the half shafts, so then I needed to replace the half shafts with '76 half shafts, which necessitated replacing the output flanges on my 901 gear box with 915 output flanges (after some minor machining) in order to have the output flanges match the inner CV joints.

You're working in the other direction -- out from the gear box, but I suspect that you'll run into similar problems. When I was done, I noticed that the new half shafts were marginally shorter then the old ones -- because the 915 gear box I suspect is a little wider then a 901/911. Anyhow, after I confirmed that the half shafts had sufficient travel for my suspension travel, I put it all together and have been happy ever since. It's been at least 3 or 4 years now.

So, I suspect that you'll need to replace the halfshafts with the 915 style (short?) half shafts, and then (potentially) replace the trailing arms if there are any fitting issues with those.

I hope that this helps.

[7693000079]

Thanks for your insight. This gives me a direction to go. Barrett